OBJECTIVE: To evaluate the responsiveness of the original low back pain specific Oswestry Disability Index (ODI) and the spinal stenosis specific Zürich Claudication Questionnaire (ZCQ), and to investigate cut-off values for clinical \"success\" for ODI and ZCQ in surgically treated patients with lumbar spinal stenosis (LSS).
METHODS: We included 601 LSS patients (218 with, 383 without degenerative spondylolisthesis) from the NORDSTEN trials. Outcome measures included ODI and ZCQ (symptom severity and physical function scales) with three alternative response parameters: scores at follow-up, absolute and relative changes from baseline to two-year follow-up. Effect size and standardised response mean evaluated internal responsiveness. External responsiveness was assessed by the Spearman rank correlation between patient-reported global perceived effect scale (GPE) and ODI and ZCQ, and receiver operating characteristics (ROC). We evaluated which cut-off values could maximise the percentage of correctly classified patients according to the GPE-anchor \"completely recovered\" / \"much improved\" for each parameter.
RESULTS: Internal and external responsiveness were high for all three indices with effect sizes, standardized response means, ROC and corresponding area under the curve > 0.8. Correlations with GPE responses were moderate (> 0.50) for absolute change and strong (> 0.67) for relative change and follow-up scores. The 30% ODI relative change cut-off correctly classified 81% of patients to \"success\", within a range of accurate cut-offs according to the GPE-anchor.
CONCLUSIONS: ODI and ZCQ demonstrate comparable responsiveness in evaluating outcomes for surgically treated LSS patients. The 30% ODI threshold was consistent with treatment \"success\" in NORDSTEN trials.
BACKGROUND: ClinicalTrials.gov; NCT02007083 10/12/2013, NCT02051374 31/01/2014 and NCT03562936 20/06/2018.

OBJECTIVE: Prior studies investigating the use of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) for treatment of degenerative lumbar conditions and concomitant sagittal deformity have not stratified patients by preoperative pelvic incidence (PI)-lumbar lordosis (LL) mismatch, which is the earliest parameter to deteriorate in mild sagittal deformity. Thus, the aim of the present study was to determine the impact of preoperative PI-LL mismatch on clinical outcomes and sagittal balance restoration among patients undergoing MI-TLIF for degenerative spondylolisthesis (DS).
METHODS: Consecutive adult patients undergoing primary 1-level MI-TLIF between April 2017 and April 2022 for DS with ≥ 6 months radiographic follow-up were included. Patient-reported outcome measures (PROMs) included the Oswestry Disability Index, visual analog scale (VAS), 12-Item Short-Form Health Survey (SF-12), and Patient-Reported Outcomes Measurement Information System at preoperative, early postoperative (< 6 months), and late postoperative (≥ 6 months) time points. The minimal clinically important difference (MCID) for PROMs was also evaluated. Radiographic parameters included PI, LL, pelvic tilt (PT), and sagittal vertical axis (SVA). Patients were categorized into balanced and unbalanced groups based on preoperative PI-LL mismatch according to age-adjusted alignment goals. Changes in radiographic parameters and PROMs were evaluated.
RESULTS: Eighty patients were included (L4-5 82.5%, grade I spondylolisthesis 82.5%, unbalanced 58.8%). Mean clinical and radiographic follow-up were 17.0 and 8.3 months, respectively. The average preoperative PI-LL was 18.8° in the unbalanced group and -3.3° in the balanced group. Patients with preoperative PI-LL mismatch had significantly worse preoperative PT (26.2° vs 16.4°, p < 0.001) and SVA (53.2 vs 9.0 mm, p = 0.001) compared with balanced patients. Patients with preoperative PI-LL mismatch also showed significantly worse PI-LL (16.0° vs 0.54°, p < 0.001), PT (25.9° vs 18.7°, p < 0.001), and SVA (49.4 vs 22.8 mm, p = 0.013) at long-term follow-up. No significant radiographic improvement was observed among unbalanced patients. All patients demonstrated significant improvements in all PROMs (p < 0.05) except for SF-12 mental component score. Achievement of MCID for VAS back score was significantly greater among patients with preoperative PI-LL mismatch (85.7% vs 65.5%, p = 0.045).
CONCLUSIONS: Although 1-level MI-TLIF did not restore sagittal alignment in patients with preoperative PI-LL mismatch, patients presenting with DS can expect significant improvement in PROMs following 1-level MI-TLIF regardless of preoperative alignment or extent of correction. Thus, attaining good clinical outcomes in patients with mild sagittal imbalance may not require addressing imbalance directly.

UNASSIGNED: The rise in degenerative lumbar spondylolisthesis (DLS) cases has led to a significant increase in fusion surgeries, which incur substantial hospitalization costs and often necessitate chronic opioid use for pain management. Recent evidence suggests that single-level low-grade DLS outcomes are comparable whether a fusion procedure or decompression alone is performed, sparking debate over the cost-effectiveness of these procedures, particularly with the advent of minimally invasive techniques reducing the morbidity of fusion. This study aims to compare chronic opioid utilization and associated costs between decompression alone and decompression with instrumented fusion for single-level degenerative lumbar spondylolisthesis.
UNASSIGNED: Using data from the PearlDiver database, a retrospective database analysis was conducted. We analyzed records of Medicare and Medicaid patients undergoing lumbar fusion or decompression from 2010 to 2022. Patient cohorts were divided into decompression alone (DA) and decompression with instrumented fusion (DIF). Chronic opioid use, pain clinic visits, and total costs were compared between the two groups at 90 days, 1 year, and 2 years post-surgery.
UNASSIGNED: Does DIF offer a more cost-effective approach to managing DLS in terms of chronic opioid use in single-level DLS patients.
UNASSIGNED: The study revealed comparable chronic opioid use and pain clinic visits between DA and DIF groups at 90 days and 1 year. However, total costs associated with opioid prescriptions as well as surgical aftercare were significantly higher in the DIF group at 90 days (p < 0.05), 1 year (p < 0.05), and 2 years (p < 0.05) post-surgery compared to the DA group.
UNASSIGNED: This study highlights the higher costs associated with DIF up to 2 years post-surgery despite comparable symptom improvement when compared to DA and DIF at the 1-year interval. DA emerges as a more financially favorable option, challenging the notion of fusion\'s cost-offsetting benefits. While further investigation is needed to understand underlying cost drivers and optimize outcomes, our findings emphasize the necessity of integrating clinical and economic factors in the management of single-level DLS.

OBJECTIVE: To compare the outcomes of decompression alone and fusion for L4-5 DLS in different age cohorts (< 70 years, ≥ 70 years).
METHODS: This retrospective cohort study included patients who underwent minimally invasive decompression or fusion for L4-5 DLS and had a minimum of 1-year follow-up. Outcome measures were: (1) patient-reported outcome measures (PROMs) (Oswestry Disability Index, ODI; Visual Analog Scale back and leg, VAS; 12-Item Short Form Survey Physical Component Score, SF-12 PCS), (2) minimal clinically important difference (MCID), (3) patient acceptable symptom state (PASS), (4) response on the global rating change (GRC) scale, and (5) complication rates. The decompression and fusion groups were compared for outcomes separately in the < 70-year and ≥ 70-year age cohorts.
RESULTS: 233 patients were included, out of which 52% were < 70 years. Patients < 70 years showed non-significant improvement in SF-12 PCS and significantly lower MCID achievement rates for VAS back after decompression compared to fusion. Analysis of the ≥ 70-year age cohort showed no significant differences between the decompression and fusion groups in the improvement in PROMs, MCID/PASS achievement rates, and responses on GRC. Patients ≥ 70 years undergoing fusion had significantly higher in-hospital complication rates. When analyzed irrespective of the surgery type, both < 70-year and ≥ 70-year age cohorts showed significant improvement in PROMs with no significant difference.
CONCLUSIONS: Patients < 70 years undergoing decompression alone did not show significant improvement in physical function and had significantly less MCID achievement rate for back pain compared to fusion. Patients ≥ 70 years showed no difference in outcomes between decompression alone and fusion.

OBJECTIVE: To compare the morphometry of paraspinal muscles in patients with degenerative spondylolisthesis (DS), isthmic spondylolisthesis (IS), and healthy individuals.
METHODS: Thirty-seven pairs of DS patients were selected using propensity score matching with IS patients, while 37 healthy individuals matched for age, sex, and BMI were selected as controls. The relative cross-sectional area (rCSA), and relative functional cross-sectional area (rfCSA) of paraspinal muscles were measured, and the degree of fatty infiltration (FI) was calculated. Based on occupational differences, the patients were also divided into worker and farmer groups, and the same measurements were taken on them.
RESULTS: At the L3/L4 level, the multifidus (MF) FI was greater in the DS and IS groups than in the control group, the erector spinae (ES) rfCSA was higher in the IS group than in the DS and control groups. At the L4/L5 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS and control groups. At the L5/S1 level, MF rfCSA was smaller in the DS and IS groups than in the control group; ES rfCSA was higher in the IS group than in the DS group. At the L3/L4, L4/L5 level, MF rfCSA were higher in the worker group than in the farmer group (p < 0.05).
CONCLUSIONS: The morphological changes in paraspinal muscles in patients with DS were dominated by selective atrophy of the MF, while in patients with IS, the morphological changes in paraspinal muscle showed selective atrophy of the MF accompanied by compensatory hypertrophy of the ES. The surgeon should consider the morphological differences in paraspinal muscle between different types of lumbar spondylolisthesis when establishing the appropriate surgical program.

OBJECTIVE: In this study, the authors aimed to determine the mid- to long-term outcomes of microendoscopic laminotomy (MEL) for lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS) and identify preoperative predictors of poor mid- to long-term outcomes.
METHODS: The authors retrospectively reviewed the medical records of 274 patients who underwent spinal MEL for symptomatic LSS. The minimum postoperative follow-up duration was 5 years. Patients were classified into two groups according to DS: those with DS (the DS+ group) and those without DS (the DS- group). The patients were subjected to propensity score matching based on sex, age, BMI, surgical segments, and preoperative leg pain visual analog scale scores. Clinical outcomes were evaluated 1 year and > 5 years after surgery.
RESULTS: Surgical outcomes of MEL for LSS were not significantly different between the DS+ and DS- groups at the final follow-up (mean 7.8 years) in terms of Oswestry Disability Index (p = 0.498), satisfaction (p = 0.913), and reoperation rate (p = 0.154). In the multivariate analysis, female sex (standard β -0.260), patients with slip angle > 5° in the forward bending position (standard β -0.313), and those with dynamic progression of Meyerding grade (standard β -0.325) were at a high risk of poor long-term outcomes.
CONCLUSIONS: MEL may have good long-term results in patients with DS without dynamic instability. Women with dynamic instability may require additional fusion surgery in approximately 25% of cases for a period of ≥ 5 years.

OBJECTIVE: This study aimed to evaluate preoperative (pre-op) radiographic characteristics and specific surgical interventions in patients with degenerative lumbar spondylolisthesis (DLS) who underwent lumbar fusion surgery (LFS), with a focus on analyzing predictors of postoperative restoration of segmental lumbar lordosis (SLL).
METHODS: A retrospective review at a single center identified consecutive single-level DLS patients who underwent LFS between 2016 and 2022. Radiographic measures included disc angle (DA), SLL, lumbar lordosis (LL), anterior/posterior disc height (ADH/PDH), spondylolisthesis percentage (SP), intervertebral disc degeneration, and paraspinal muscle quality. Surgery-related measures included cage position, screw insertion depth, spondylolisthesis reduction rate, and disc height restoration rate. A change in SLL ≥ 4° indicated increased segmental lumbar lordosis (ISLL), and unincreased segmental lumbar lordosis (UISLL) < 4°. Propensity score matching was employed for a 1:1 match between ISLL and UISLL patients based on age, gender, body mass index, smoking status, and osteoporosis condition.
RESULTS: A total of 192 patients with an average follow-up of 20.9 months were enrolled. Compared to UISLL patients, ISLL patients had significantly lower pre-op DA (6.78° vs. 11.84°), SLL (10.73° vs. 18.24°), LL (42.59° vs. 45.75°), and ADH (10.09 mm vs. 12.21 mm) (all, P < 0.05). ISLL patients were predisposed to more severe intervertebral disc degeneration (P = 0.047) and higher SP (21.30% vs. 19.39%, P = 0.019). The cage was positioned more anteriorly in ISLL patients (67.00% vs. 60.08%, P = 0.000), with more extensive reduction of spondylolisthesis (- 73.70% vs. - 56.16%, P = 0.000) and higher restoration of ADH (33.34% vs. 8.11%, P = 0.000). Multivariate regression showed that lower pre-op SLL (OR 0.750, P = 0.000), more anterior cage position (OR 1.269, P = 0.000), and a greater spondylolisthesis reduction rate (OR 0.965, P = 0.000) significantly impacted SLL restoration.
CONCLUSIONS: Pre-op SLL, cage position, and spondylolisthesis reduction rate were identified as significant predictors of SLL restoration after LFS for DLS. Surgeons are advised to meticulously select patients based on pre-op SLL and strive to position the cage more anteriorly while minimizing spondylolisthesis to maximize SLL restoration.

Studies have demonstrated increased risk of adjacent segment disease (ASD) after open fusion with adjacent-level laminectomy, with rates ranging from 16%-47%, potentially related to disruption of the posterior ligamentous complex. Minimally invasive surgical (MIS) approaches may offer a more durable result. We report institutional outcomes of simultaneous MIS transforaminal lumbar interbody fusion (MISTLIF) and adjacent-level laminectomy for patients with low grade spondylolisthesis and ASD.
Retrospective analysis was performed on patients who underwent MISTLIF with adjacent level laminectomy to treat grade I-II spondylolisthesis with adjacent stenosis at a single institution from 2007-2022.
A total of 34 patients met criteria, with mean follow-up of 23.1 months. In total, 37 levels were fused and 45 laminectomies performed. In this group, 21 patients received a single level laminectomy and single-level MISTLIF, 10 patients received a 2-level laminectomy and single-level MISTLIF, 2 patients received a single-level laminectomy and 2-level MISTLIF, and 1 patient received a 2-level laminectomy and 2-level MISTLIF. Three (8.8%) patients experienced clinically significant postoperative ASD requiring reoperation. Three other patients required reoperation for other reasons. Multiple logistic regression did not reveal any association between development of ASD and surgical covariates.
MISTLIF with adjacent-level laminectomy demonstrated a favorable safety profile with rates of postoperative ASD lower than published rates after open fusion and on par with the published rates of ASD from MISTLIF alone. Future prospective studies may better elucidate the durability of adjacent-level laminectomies when performed alongside MISTLIF, but retrospective data suggests it is safe and durable.

Background and objective The Meyerding classification system remains the most common classification system for spondylolisthesis based on the percentages of vertebral translation. However, the majority of patients with degenerative disease fall into Grade 1, limiting its utility in this subset of patients. The Clinical and Radiographic Degenerative Spondylolisthesis (CARDS) classification system provides a simple radiographic framework for classifying degenerative lumbar spondylolisthesis (DLS) patients by incorporating disc height, kyphosis, and anterior translation. The purpose of this study was to evaluate how clinical characteristics, treatments, and outcomes vary across different CARDS groups in patients undergoing one- or two-level lumbar fusion for DLS. Methods The patients were classified into one of the following four CARDS groups - Type A: advanced disc space collapse with no evidence of kyphosis; Type B: partially preserved disc space with less than 5.0 mm of translation; Type C: partially preserved disc space with greater than 5.0 mm of translation; and Type D: kyphotic alignment. Univariate analyses were performed to compare demographics, symptoms, clinical outcomes, and Patient-Reported Outcomes Measurement Information System (PROMIS) physical (PH) and mental health (MH) scores across groups. Results Ninety-one patients were included in the study. Based on the CARDS classification, there were three (3%) Type A patients, 25 (28%) Type B, 58 (64%) Type C, and five (5%) Type D. No significant differences in baseline demographics, symptom duration, or PROMIS scores were observed across groups. Interbody utilization varied, ranging from 19% in CARDS C (n=11) to 60% in CARDS B (n=15) and D (n=3) patients (p=0.005). Thirty-day clinical outcomes were similar across groups. At an average follow-up of 8.9 months, improvements in PROMIS PH and MH scores and rates of clinically significant improvement were similar across groups. Conclusions Based on our findings, patients undergoing lumbar fusion for DLS present with similar demographic and clinical characteristics and experience similar clinical and patient-reported outcomes when stratified using the CARDS classification system. Posterolateral fusion (PLF) can be effective for various radiographic presentations of DLS. Further research is warranted to assess the utility of CARDS in preoperative planning.

BACKGROUND: Clinical guidelines, developed in concordance with the literature, are often used to guide surgeons\' clinical decision making. Recent advancements of large language models and artificial intelligence (AI) in the medical field come with exciting potential. OpenAI\'s generative AI model, known as ChatGPT, can quickly synthesize information and generate responses grounded in medical literature, which may prove to be a useful tool in clinical decision-making for spine care. The current literature has yet to investigate the ability of ChatGPT to assist clinical decision making with regard to degenerative spondylolisthesis.
OBJECTIVE: The study aimed to compare ChatGPT\'s concordance with the recommendations set forth by The North American Spine Society (NASS) Clinical Guideline for the Diagnosis and Treatment of Degenerative Spondylolisthesis and assess ChatGPT\'s accuracy within the context of the most recent literature.
METHODS: ChatGPT-3.5 and 4.0 was prompted with questions from the NASS Clinical Guideline for the Diagnosis and Treatment of Degenerative Spondylolisthesis and graded its recommendations as \"concordant\" or \"nonconcordant\" relative to those put forth by NASS. A response was considered \"concordant\" when ChatGPT generated a recommendation that accurately reproduced all major points made in the NASS recommendation. Any responses with a grading of \"nonconcordant\" were further stratified into two subcategories: \"Insufficient\" or \"Over-conclusive,\" to provide further insight into grading rationale. Responses between GPT-3.5 and 4.0 were compared using Chi-squared tests.
RESULTS: ChatGPT-3.5 answered 13 of NASS\'s 28 total clinical questions in concordance with NASS\'s guidelines (46.4%). Categorical breakdown is as follows: Definitions and Natural History (1/1, 100%), Diagnosis and Imaging (1/4, 25%), Outcome Measures for Medical Intervention and Surgical Treatment (0/1, 0%), Medical and Interventional Treatment (4/6, 66.7%), Surgical Treatment (7/14, 50%), and Value of Spine Care (0/2, 0%). When NASS indicated there was sufficient evidence to offer a clear recommendation, ChatGPT-3.5 generated a concordant response 66.7% of the time (6/9). However, ChatGPT-3.5\'s concordance dropped to 36.8% when asked clinical questions that NASS did not provide a clear recommendation on (7/19). A further breakdown of ChatGPT-3.5\'s nonconcordance with the guidelines revealed that a vast majority of its inaccurate recommendations were due to them being \"over-conclusive\" (12/15, 80%), rather than \"insufficient\" (3/15, 20%). ChatGPT-4.0 answered 19 (67.9%) of the 28 total questions in concordance with NASS guidelines (P = 0.177). When NASS indicated there was sufficient evidence to offer a clear recommendation, ChatGPT-4.0 generated a concordant response 66.7% of the time (6/9). ChatGPT-4.0\'s concordance held up at 68.4% when asked clinical questions that NASS did not provide a clear recommendation on (13/19, P = 0.104).
CONCLUSIONS: This study sheds light on the duality of LLM applications within clinical settings: one of accuracy and utility in some contexts versus inaccuracy and risk in others. ChatGPT was concordant for most clinical questions NASS offered recommendations for. However, for questions NASS did not offer best practices, ChatGPT generated answers that were either too general or inconsistent with the literature, and even fabricated data/citations. Thus, clinicians should exercise extreme caution when attempting to consult ChatGPT for clinical recommendations, taking care to ensure its reliability within the context of recent literature.